1. Technical Field
The disclosure relates to an optical element and a preparation method thereof. More particularly, the disclosure relates to a polarizer plate and a preparation method thereof.
2. Description of Related Art
One of the components of liquid crystal displays (LCD) is the polarizer plate. The cost of the polarizer plate is about 6%-18% of the total cost of LCDs. The polarizer film of the polarizer plate commonly is the stretched polyvinyl alcohol (PVA) film. Since optical properties of the stretched PVA film are easily affected by heat and moisture, additional two protection films are needed to sandwich the PVA film to protect the stretched PVA from damage.
In the present, the most usual materials for the protection films is triacetate cellulose (TAC) or cycloolefin polymer (COP), both are quite expensive. Moreover, the hydrogel is needed to adhere the protection films to the PVA film. In order to increase the adhesive strength between the PVA film and the protection films, additional treatment to the protection film is needed, such as the TAC films need strong base etching treatment and the COP films need corona treatment. The preparation process of the polarizer plate is quite complicated. Therefore, an object of the present invention is providing a novel polarizer plate in which the protection film is replaced by the acrylic resin protection film. And an object of the present invention is providing a novel polarizer preparation method in which the acrylic resin protection film can be also used as an adhesive without using the hydrogel to adhere to the PVA film. In the preparing method of the novel polarizer, a glass transition temperature of the acrylic resin is preferred higher than 50° C. to avoid the acrylic resin soften at the room temperature and provide the sufficient protection. Moreover, the glass transition temperature of the acrylic resin is preferred not more than 100° C. When the acrylic resin have a higher glass transition temperature the is, acrylic resin protection film must be laminated at higher temperature and there maybe a possibility of exerting a damage by heating on the polarizer.